Arc lamp



1,581 729 April 2@ 1926' H. GERDIEN Er AL ARC LAMP Filed Nov. 21, 1924 Patented Apr. 20, 1926.

UNITED STATES PATENT OFFICE.

HANS GEnmEN AND ALBERT LOTZ, E BERLIN-GRUNEWALD, GERMANY, assrenons T0 SIEMENS & HALSKE. AKTIENGESELLSCHAFT. or SIEMENSSTADT, NEAR BERLIN am) ELSEWHERE, A CORPORATION or GERMANY.

ARC LAMP.

Application filed November 21, 1924.. Serial No. 751,268.

To all whom it 'may concern:

Be it known that we, HANS GERDIEN and Ann nrr Lo'rz, citizens of the German Empire, residing at .Berlin-Grunewald, Germany, Berlin-Grnnewald, Germany, respectively, have invented certain new and useful Improv'cments in Aro'Lam s (for which we have filed application in ermany on November 19, 1923), of which the following is a specification.

Our invention relates toimprovements. in are lamps. The object of our invention is to increase the intrinsic brilliancy of such lamps. In order to increase the intrinsic brilliancy of an arc lamp it is necessary to contract the arc. The contraction of the are is particularly reliable when it is el'jfected by means of a layer or film of liquid.

According to our invention this layer or film of liquid is obtained by introducing the liquid into a revolving tube. The centrifugal forces generated during'the rotation of the tube effect the formation of an extremely uniform layer or film of liquid upon the inner wall of the'tube which contracts the are with certainty and prevents its spreading to the outer surface of'the anode.

In the drawing affixed to this specification and forming part thereof two embodiments 3 of our invention are illustrated by way of example.

\ Fig. 1, is a longitudinal section through the improved are lamp.

Fig. 2, a cross-section of the same on the an line AB in Fig. 1.

- Fig. 3, a longitudinal section of a modified construction.

Similar parts are. indicated by the same letters of reference in all the figures of the drawing, and

1 Fig. 4 is a right end view shown ire-Figs. hand 3.

Referring to Fig. 1 it will be seen that the positive carbon 1 is slidably disposed in a guide bushing 5 of the casing 4 and surrounded by a tube 2 of slightly largerinte-rnal diameter.- This tube 2 is rovided with a flaring extension 3 which ts accurately into a conical or flared bore 19 of the casing 4. The tube 2 is adaptedto be rotated by means of a cord pulleyt). Through the pipe 6 water serving for the covering of the inner walls of the tube 2 entcrstthe annularchannel or hamber 7 whence it passes of the lamp of the anode-axis.

into the interior of the tube 2 by the tangential bores 8 which are clearly shown in Fig. 2. During the rotation of the tube 2 the water spreads in the form of a thin layer or line film over the inner wall of the tube 2 owing to the centrifugal forces generated and ultimately flows out of the extension 3. Alli-he parts of. the tube ex- ..posed to the are are thus covered with a thin film of water. The cathode consists of three carbons 13 inclined to one another at equal angles towards the anode, as shown in Fig.

'4, which pcrn'iits the unobstructed emanation of light from the anode in the direction By means of a few turns of wire 14- traversed by a current, a magnetic field is generated which causes the arc to travel over the three negative electrodes whereby a uniform consun'iption of the electrodes is attained. From the terminal 12 connected with the positive pole the current passes througlrthe turns 14 to the terminal 18 of the casing -1 and from here across the bushing 5 to the positive electrode.

Fig. 3 illustrates a slightly modified construction. Here the carbon 1 is firmly connected with the tube 2 so that the carbon revolves'with the tube. The current is in this case introduced bythe sliding contactelement 10 which is pressed against the tube 2 by a helical spring 11.

lVhat we claim is z- 1. In an electric arc lamp, in combination.

- a pair of electrodes, means for forming an electric are between said electrodes, a rotatable tube surrounding said arc, means for imparting rotary motion to said tube and means for maintaining a inner wall of said tube.

2. In an elect "c are lamp, incombination, a pair of electrodes, means for forming. an electric ai'c.,.-bet\\'ee n'-said electrodes, a rota- .table tube surrounding said are, means for imparting rotary motion to said tube, and means for introducing liquid into said tube for forming a film on the inner'wallthereof.

3. In an electric arc lamp, in combination, a pair of electrodes, means for rotating one of said electrodes, means 'for forming an electric are between said electrodes,a rotatable tube surrounding said arc, means for imparting ,rotary motion to said tube and means for maintaining a film of liquid on the inner wall of said tube.

film of liquid on the 4. In an electric arc lamp, in combination,

. a pair of electrodes, means for rotating one of said electrodes, means for forming an electric arc between said electrodes, a r0- tatable tube surrounding said arc, means for imparting rotary motion to said tube,

and means for introducing liquid required into said tube for forming a film on the intatable, means for forming an electric are between said electrodes, a tube surrounding said are and adapted to be rotated together with said anode, means for imparting rotary motion to said tube and mean for maintaining a film of liquid on the inner wall of said tube.

In testimony whereof we aflix our signatures.

HANS GERDIEN. ALBERT LOTZ. 

